12155191220 has 24 divisors (see below), whose sum is σ = 25849017600. Its totient is φ = 4800530592.

The previous prime is 12155191219. The next prime is 12155191231. The reversal of 12155191220 is 2219155121.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 3845000 + ... + 3848159.

It is an arithmetic number, because the mean of its divisors is an integer number (1077042400).

Almost surely, 2^12155191220 is an apocalyptic number.

12155191220 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

12155191220 is an abundant number, since it is smaller than the sum of its proper divisors (13693826380).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

12155191220 is a wasteful number, since it uses less digits than its factorization.

12155191220 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7693247 (or 7693245 counting only the distinct ones).

The product of its (nonzero) digits is 1800, while the sum is 29.

The spelling of 12155191220 in words is "twelve billion, one hundred fifty-five million, one hundred ninety-one thousand, two hundred twenty".